Development of a Thin Layer Chromatography Method for the Qualitative Detection of Pregabalin in Human Urine
International Journal of Medical Toxicology and Forensic Medicine,
Vol. 16 (2026),
1 Dey 2026
,
Page 1-5
https://doi.org/10.22037/ijmtfm.v16.52078
Abstract
Background: Pregabalin (PGB) misuse represents a growing public health concern in Algeria, where routine urinary immunoassay screening is limited by elevated cut-off values (≥ 500 µg/L) and cross-reactivity with structurally related compounds, notably gabapentin. This study aimed to develop and validate a simple, low-cost thin-layer chromatography (TLC) method for the qualitative detection of pregabalin in human urine.
Methods: Urine samples were acidified, extracted with ethyl acetate, and spotted onto silica gel plates. Development used a methanol–ammonia mobile phase (98.5:1.5, v/v), and detection was achieved by spraying with ninhydrin reagent followed by heating at 60°C, yielding a characteristic violet spot at Rf = 0.56.
Results: The method demonstrated excellent selectivity (6/6 blank matrices), full specificity against a panel of 30 drugs and substances of abuse, a limit of detection (LOD) of 100 µg/L, and urine stability at −20°C for seven days. Applied to 87 clinical samples, TLC identified 10 false-negative immunoassay results and resolved 7 gabapentin-related false-positive cases, confirming its diagnostic value in resource-limited toxicology settings.
Conclusion: This validated, chloroform-free TLC method provides a cost-effective, selective, and highly sensitive alternative for urinary pregabalin screening, making it an ideal tool for resource-limited toxicology laboratories.
- Forensic toxicology, Drug abuse, Misuse, Immunoassay, Pregabalin
How to Cite
References
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